The government must carry out an independent assessment of the ability of consumers to pay an extra £250bn in household bills over the next 15 years to modernise Britain's ageing infrastructure, MPs have said.

Warning that the poorest households would be hit hard by years of above-inflation increases, members of the influential public accounts committee (PAC) said consumers would be expected to meet two-thirds of the £375bn total cost of major upgrades to services including energy, water, communications and transport.

The government has forecast that energy bills will rise by 18% in real terms by 2030 compared with last year, and the committee said there should be a more "joined-up" approach by government departments and regulators to take into account the plight of consumers and the affordability of energy and rail costs.

Margaret Hodge, Labour MP and chair of the committee, said: "No one in government is taking responsibility for assessing the overall impact of this investment on consumer bills and whether consumers will be able to afford to pay.

"No one seems to be sticking up for the consumer in all this. This is of particular concern given that the poorest households are hit hardest by increases in bills. Poorer households spend more of their incomes on household bills relative to richer households, meaning that funding infrastructure through bills is more regressive than doing so through taxation."

The committee also warned the prolonged uncertainty caused by government policies could add to rising energy bills, with investment in new power stations being delayed and a "lack of urgency" in replacing coal-fired plants.

The Treasury has £375bn of infrastructure projects in the pipeline up to 2030 to replace ageing assets, support growth, meet the demands of a growing population and comply with European regulations and climate change targets. Its National Infrastructure Plan (NIP) was published in December, setting out the detail and timescale for the investment in energy, transport, communications and water projects.

Two-thirds of this investment will come from private companies and be paid for by consumers through utility bills and charges such as rail fares.

Publishing her committee's report, Investment: the impact on consumer bills', Hodge said: "A staggering £375bn of investment is needed to replace the country's ageing infrastructure, help meet policy commitments such as climate change targets, and meet the long-term needs of a growing population. It is the consumer – through their various bills – that is expected to fund at least two-thirds of this investment where the infrastructure is financed, built, owned and operated by private companies. Currently, consumers rely solely on government and regulators to protect their interests. But it doesn't take much nous to work out that this is going to have a tough impact on the consumer."

While median household incomes "did not rise significantly" in the decade to 2011, energy bills rose – in real terms – by 44% and water bills by 21%, she said. "High levels of new investment in infrastructure mean bills and charges are likely to continue to rise significantly in the future."

The committee called on the Treasury "to produce and publish an assessment of the long-term affordability of bills across the sectors. They need to establish with departments and regulators who is responsible for what in each sector when it comes to assessing the long-term affordability of bills, and pull all the information together."

Neil Duncan-Jordan at the National Pensioners Convention, which describes itself as Britain's biggest pensioner organisation, backed the committee's call.

He said recent official statistics showed the fuel poverty crisis was getting worse, and the UK's poor-quality housing stock was exacerbating the problem. "Support for older people just hasn't kept pace with rising energy costs," he said. "We would make the point more generally that consumers have taken a pasting from the private energy companies."

The Treasury said: "The country will pay a heavy price if we don't invest in the infrastructure essential for our future. The National Infrastructure Plan provides unprecedented certainty about what those investments are and making sure they are built in a way that delivers value for consumers and taxpayers is at the centre of it. The analysis in the PAC report fails to make a proper assessment of this.

"We uphold a robust independent regulatory regime with powers to ensure the interests of consumers are properly protected, including the establishment of a new Competition and Markets Authority this year."

The report also warns: "The complexity and changing nature of government policies, particularly in the energy sector, risk delaying much-needed investment." MPs heard there was planning consent for 15 gigawatts of gas-powered electricity generation but "investors are not going ahead due to a combination of unfavourable market prices for gas and electricity, and lack of certainty with regard to the government's electricity market reforms".